Purpose Of The Heat Pump; Application; Operating Principle; Scope Of Delivery - Buderus WPL 91ARM Montage- Und Gebrauchsanweisung

2 Purpose of the Heat
Pump

2.1 Application

The air-to-water heat pump is to be used exclusively for the heat-
ing of heating water. It can be used in newly built or previously
existing heating systems.
The heat pump is suitable for mono energy and bivalent opera-
tion down to an external temperature of -20 °C.
Proper defrosting of the evaporator is guaranteed by maintaining
a heating water return flow temperature of more than 13 °C dur-
ing continuous operation.
The heat pump is not designed for the increased heat consump-
tion required when a building is being dried out. The additional
heat consumption should be met using special devices provided
by the customer. If a building is to be dried out in autumn or win-
ter, we recommend installing an additional heating element
(available as an accessory).
ATTENTION!
The device is not suitable for operation with a frequency converter.

2.2 Operating Principle

Surrounding air is drawn in by the ventilator and fed via the evap-
orator (heat exchanger). The evaporator cools the air, i.e. it ex-
tracts heat from it. This extracted heat is then transferred to the
working medium (refrigerant) in the evaporator.
The heat is "pumped" to a higher temperature level by increasing
its pressure with the aid of the electrically driven compressors. It
is then transferred to the heating water using the liquifier (heat
exchanger).
Electrical energy is used to raise the temperature of the heat in
the environment to a higher level. Because the energy extracted
from the air is transferred to the heating water, this type of device
is called an air-to-water heat pump.
The air-to-water heat pump consists of the main components
evaporator, ventilator and expansion valve, as well as the low-
noise compressors, liquifier and electrical control system.
At low ambient temperatures, humidity accumulates on the evap-
orator in the form of frost reducing the transfer of heat. The evap-
orator is defrosted automatically by the heat pump as required.
Steam may be emitted from the air outlet depending on the at-
mospheric conditions.
3

Scope of Delivery

3.1 Basic Device

The heat pump is of compact design and is supplied complete
with the components listed below.
R290 (propane) is used as refrigerant.
1) Evaporator
2) Ventilator
3) Switch box
4) Compressor
5) Liquifier
6) Expansion valve
3.1
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